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How Fast Can Cities Grow?

Beijing Railway Station

One of the defining traits of humanity is our social nature. Living and working together has been a large factor in our survival. For thousands of years we’ve been living together in cities. As technology increases so does the size and scope of our cities. How fast can cities grow? Listen to this Question Your World radio report produced by the Science Museum of Virginia to learn more.

Currently we have 7.3 billion people on this planet. Nearly 54% of our species lives in cities. The planning and growth of our cities have remarkable impacts ranging from how we impact the natural world to how we develop cultures and traditions. Studying cities is a relatively new discipline, but similar to our population, this study has been growing rapidly as well. Our perspective from the ground gives us a limited view of the full scope of our growth. To study cities on the grandest perspective we must get up higher for the ultimate bird’s eye view.

On October 4, 1957, Sputnik became the first satellite launched into space. The Soviet space program kicked off the first of many firsts in satellite technology. Currently there are thousands of satellites orbiting the Earth. Today’s fleet of satellites assist in bringing us GPS, television broadcasts, internet service, weather tracking data, vital Earth studies information and beyond. Occasionally these satellites also bring us interesting information which allows us to see how our cities are growing.

NASA launched the QuickSCAT satellite in the year 2000. The primary purpose was to gauge wind speeds and better understand weather patterns. Part of this involved gathering data on cities and the surrounding winds. Over the years QuickSCAT brought us lots of valuable information until a mechanical failure rendered it useless in 2009. However, before it entered permanent retirement, it took one final shot of the city of Beijing. Recently scientists stumbled upon a lot of this data and noticed something quite remarkable. By comparing the data of Beijing from 2000 and 2009 they noticed that the city had quadrupled in size in just 9 short years. The roadways, density of urban living space, power grids, and beyond had all noticeable expanded a large amount. Though this data was initially created for wind-related purposes this data can now be used by urban planners and climate scientists to better understand the full impact that city growth can have on surrounding areas.

As the population increases, more and more cities will need to adapt to the growing needs of urban area. These changes will have profound impacts on how we allocate energy, farm land, transportation needs, and beyond. Satellite images can be used as a valuable tool to see how urban spaces will impact the surrounding areas while helping urban planners better see the metrics they need to develop their city’s future.

Our growing global family has a lot of challenges up ahead. We have yet to provide adequate resources for over half the planet's population. There are energy issues that still need to be addressed in most countries. The impacts of climate change will need to be addressed by the current and future generations. Having more information and education on these topics is vital to forming solutions for these issues. This wind-studying satellite’s data on urban growth is a great example of how various disciplines can come together to acquire new knowledge on existing issues. The hard part is funding new research, hiring the staff needed to process information, identifying problems, working up solutions, and getting the support of governments and voters. The rest, similar to the QuickSCAT mission, is a breeze.